372 research outputs found
Optical networking special issue based on selected papers of IEEE ANTS 2015
In Priority-based content processing with Q-routing in Information Centric Networking (ICN), Sibendu Paul, Bitan Banerjee, Amitava Mukherjee and Mrinal K. Naskar address content management issue in a cache with finite storage capability in ICN by proposing an efficient content management policy that changes a router to a self-sustained cache. A novel algorithm based on Q-routing is proposed to determine the order of service for content packets in the buffer of a cache and find next node toward the destination with minimum propagation delay
On Supporting Small M2M Data Transmissions in LTE/LTE-A Networks
In Machine-to-Machine (M2M) applications, devices monitor events (e.g., temperature, inventory
level), which is relayed through a communication network infrastructure (e.g. Internet, LTE) to an
application (software program running on a server connected to the Internet), that translates the
monitored event into some meaningful information to be able to take collaborative decisions with
limited or no human intervention.
With the availability of IPv6 address, it is possible to interconnect everything in this universe.
By using the concept of interconnecting things, several applications can be envisioned to make the
world smarter. Internet of Things (IoT) is a paradigm whose aim is to implement the concept of
interconnection of everything by using all possible technologies and others means. M2M communica-
tion is one of the components of Internet of Things (IoT) whose goal is to make the communication
smooth and seamless between any two networking enabled devices. According to the researchers by
the end of 2014, 1.5 billion devices and by the end of 2020, 20 billion devices will be part of M2M
communication
IP Flow Mobility based Offload in LTE Wi-Fi Interworking Scenario
Mobile data traffic has seen an exponential growth in the past few years with the trend expected
to continue. LTE as a standalone cellular network is unable to keep pace with the increasing
traffic demands. In the meanwhile, wireless LAN has proven itself as an economical wireless access
technology. 3GPP has thus been encouraged to standardize the integration of Wi-Fi networks with
LTE. This opens up numerous opportunities to study data offloading and mobility management
protocols. One of the newer offloading technique is known as IP Flow Mobility, where individual
IP flows are migrated from one network to the other without affecting other flows belonging to the
same IP session. In this thesis work, a framework has been developed on ns-3 which supports flow
mobility between LTE and Wi-Fi. This framework is based on PMIPv6.
This flow mobility framework provides an opportunity to implement various algorithms to decide
which network is used to serve which flows while trying maintain a balance between bandwidth
utilization and user satisfaction. One such algorithm has been proposed here for a network consisting
of LTE and Wi-Fi. This algorithm calculates a quality value for each flow on the network using
parameters like flow type, SNR, velocity of the user, etc and tries to offload these flows onto either
network based on the flow’s quality value.
A simple simulation is carried out which validates the implementation of the framework, where
a TCP flow is migrated to a Wi-Fi network from the LTE network based on the SNR of the Wi-Fi
network. It also shows how the velocity of a UE affects the percentage of offload which can be
achieved and how the flow’s performance is affected by the offload
DYNAMO-MAS: a multi-agent system for ontology evolution from text
International audienceManual ontology development and evolution are complex and time-consuming tasks, even when textual documents are used as knowledge sources in addition to human expertise or existing ontologies. Processing natural language in text produces huge amounts of linguistic data that need to be filtered out and structured. To support both of these tasks, we have developed DYNAMO-MAS, an interactive tool based on an adaptive multi-agent system (adaptive MAS or AMAS) that builds and evolves ontologies from text. DYNA-MO-MAS is a partner system to build ontologies; the ontologist interacts with the system to validate or modify its outputs. This paper presents the architecture of DYNAMO-MAS, its operating principles and its evaluation on three case studies
Architectural Challenges and Solutions for Collocated LWIP - A Network Layer Perspective
Achieving a tighter level of aggregation between
LTE and Wi-Fi networks at the radio access network (a.k.a.
LTE-Wi-Fi Aggregation or LWA) has become one of the most
prominent solutions in the era of 5G to boost network capacit
y
and improve end user's quality of experience. LWA offers
flexible resource scheduling decisions for steering user tr
affic
via LTE and Wi-Fi links. In this work, we propose a Collocated
LTE/WLAN Radio Level Integration architecture at IP layer
(C-LWIP), an enhancement over 3GPP non-collocated LWIP
architecture. We have evaluated C-LWIP performance in vari
ous
link aggregation strategies (LASs). A C-LWIP node (
i.e.
, the node
having collocated, aggregated LTE eNodeB and Wi-Fi access
point functionalities) is implemented in NS-3 which introd
uces a
traffic steering layer (
i.e.
, Link Aggregation Layer) for efficient
integration of LTE and Wi-Fi. Using extensive simulations,
we
verified the correctness of C-LWIP module in NS-3 and evaluat
ed
the aggregation benefits over standalone LTE and Wi-Fi netwo
rks
with respect to varying number of users and traffic types. We
found that split bearer performs equivalently to switched b
earer
for UDP flows and switched bearer outperforms split bearer in
the case of TCP flows. Also, we have enumerated the potential
challenges to be addressed for unleashing C-LWIP capabilit
ies.
Our findings also include WoD-Link Aggregation Strategy whi
ch
is shown to improve system throughput by 50% as compared to
Naive-LAS in a densely populated indoor stadium environmen
t
FLEXCRAN: Cloud radio access network prototype using OpenAirInterface
In this demo, we describe the realization of cloud radio access network (C-RAN) prototype using OpenAirInterface (OAI) software and commodity hardware. The deployment of the centralized baseband processing on the remote cloud center (RCC), and the remote radio units (RRU), connected over Ethernet fronthaul is demonstrated. Further, the demo illustrates the flexibility in deploying several cellular radio access network protocol split architectures using OAI
Unveiling metabolic vulnerability and plasticity of human osteosarcoma stem and differentiated cells to improve cancer therapy
Defining the metabolic phenotypes of cancer-initiating cells or cancer stem cells and of their differentiated counterparts might provide fundamental knowledge for improving or developing more effective therapies. In this context we extensively characterized the metabolic profiles of two osteosarcoma-derived cell lines, the 3AB-OS cancer stem cells and the parental MG-63 cells. To this aim Seahorse methodology-based metabolic flux analysis under a variety of conditions complemented with real time monitoring of cell growth by impedentiometric technique and confocal imaging were carried out. The results attained by selective substrate deprivation or metabolic pathway inhibition clearly show reliance of 3AB-OS on glycolysis and of MG-63 on glutamine oxidation. Treatment of the osteosarcoma cell lines with cisplatin resulted in additive inhibitory effects in MG-63 cells depleted of glutamine whereas it antagonized under selective withdrawal of glucose in 3AB-OS cells thereby manifesting a paradoxical pro-survival, cell-cycle arrest in S phase and antioxidant outcome. All together the results of this study highlight that the efficacy of specific metabolite starvation combined with chemotherapeutic drugs depends on the cancer compartment and suggest cautions in using it as a generalizable curative strategy
Conditionally immortalized human proximal tubular epithelial cells isolated from the urine of a healthy subject express functional calcium-sensing receptor
The calcium-sensing receptor (CaSR) is a G protein-coupled receptor, which plays an essential role in regulating Ca(2+) homeostasis. Here we show that conditionally immortalized proximal tubular epithelial cell line (ciPTEC) obtained by immortalizing and subcloning cells exfoliated in the urine of a healthy subject expresses functional endogenous CaSR. Immunolocalization studies of polarized ciPTEC revealed the apical localization of the receptor. By Western blotting of ciPTEC lysates, both monomeric and dimeric forms of CaSR at 130 and ∼250 kDa, respectively, were detected. Functional studies indicated that both external calcium and the positive CaSR allosteric modulator, NPS-R568, induced a significant increase in cytosolic calcium, proving a high sensitivity of the endogenous receptor to its agonists. Calcium depletion from the endoplasmic reticulum using cyclopiazonic acid abolished the increase in cytosolic calcium elicited by NPS-R568, confirming calcium exit from intracellular stores. Activation of CaSR by NPS-R significantly reduced the increase in cAMP elicited by forskolin (FK), a direct activator of adenylate cyclase, further confirming the functional expression of the receptor in this cell line. CaSR expressed in ciPTEC was found to interact with Gq as a downstream effector, which in turn can cause release of calcium from intracellular stores via phospholipase C activation. We conclude that human proximal tubular ciPTEC express functional CaSR and respond to its activation with a release of calcium from intracellular stores. These cell lines represent a valuable tool for research into the disorder associated with gain or loss of function of the CaSR by producing cell lines from patients
DIABETIC RETINOPATHY: IMPORTANCE OF PRIMARY CARE PHYSCIAN IN SCREENING
Objective: The objective of  this study is importance of primary care physician in screening diabetic retinopahy  patientsMaterial and Methods : Patients of type-2 diabetes mellitus attending diabetic clinic in melaka manipal medical college , malaysia were prospectively reviewed. Risk factors associated  in study population were assessed by biochemical parameters, clinical examination , retinal photographs and referred to ophthalmology clinic.Results: The prevalence of non proliferative and proliferative diabetic retinopathy with type-2 diabetic patients was 17% and 1%  with history of decreased in vision above age group of 50 years . In addition the risk factors in the study group associated with the development of diabetic retinopathy are  uncontrolled HbA1c levels ( 27%) , high BMI (38% ), increased total cholesterol (9% ) , uncontrolled fasting blood sugar levels (47%),  and increased duration of diabetes.Conclusion: Diabetic retinopahy is highly prevalent in patients with type-2 diabetes mellitus. Our findings indicates primary care physicians are  well educated in regards to diabetic eye disease and in identification of risk factors due to number of years experience.Keywords: Proliferative and non proliferative diabetic retinopathy, risk factors, visual disability, type -2 diabetes mellitusÂ
Adaptive RACH Congestion Management to Support M2M Communication in 4G LTE Networks
Machine to machine communication (M2M) or machine type communication (MTC) facilitates communication of two network enabled devices, without any human intervention, to take some intelligent decision based on the interaction of devices. Because of ubiquitous coverage and global connectivity, cellular networks are playing a major role in the deployment of M2M communications. Due to some unique characteristics of M2M communication, supporting M2M applications in cellular networks is very challenging. One of such challenge is congestion in radio access network (RAN) during RACH procedure. This is because of the fact that there are large numbers of M2M devices which access the radio network at the same time. As a solution, we propose an adaptive RACH congestion management function (ARC) which specifies congestion handling method to be used by all M2M devices based on the current congestion condition of the networ
- …